Vinyl halide polymers stabilized with phosphites and benzoic acid esters



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VINYL HALIDE POLYMER STABILIZED WITH PHOSPHITES BENZOKC ACID ESTERSJoseph R. Darby, Webster Groves, and Paul R. Graham, Richmond Heights,Mm, assignors to Monsanto Chem= ical Company, St. Louis, Mo., acorporation of Data were No Drawing. Application July 16, 1956 SerialNo. 597,870

16 Claims. (Cl. 260-23) This invention relates to a novellightstabilizer mixture for halogen-containing resins.

In accordance with this invention. it has been found that the lightstability properties of halogen-containing resins are substantiallyimproved by incorporating therein a mixture of a tri(hydrocarbon)phosphite and a hydroxy-benzoic acid ester of the structure C-O-R a L. A

where. m is an integer from 1 to 2, where nv is an integer from to 1,and where R is an aromatic radical. It is particularly preferred that mbe one, that n be zero, and that Rv be an aromatic hydrocarbon radical,such as phenyl, methylphenyl, ethylphenyl, isopropylphenyl, naphthyl,biphenyl, and the like. It is to be understood, however, that R maycontain oxygen atoms in addition to carbon and hydrogen atoms, e.g. Rmay be hydroxyphenyl, methoxyphenyl, dihydroxyphenyl, dimethoxyphenyl,hydroxymethoxyphenyl, etc.

This new andnovel light stabilizer mixture has. been found particularlyuseful in enhancing the light stability properties of the heat stablehalogen-containing resins described in US. 2,671,064 which comprise ahalogencontaining resin, a plasticizer therefor, a cadmium salt of anorganic acid and an epoxy compound containing one or more groups of thestructure The following-examples are illustrative of'this invention butin no manner are to be'construed as limitative thereof.

Compositions comprising, respectively,

are prepared by mixing polyvinyl chloride with the respectiveingredients in amounts set forth above on difierential speed rolls at aroll temperature of 160 C. to form a homogeneous composition which isremoved from the roll in the form of crude sheets. From the crude sheetsthere are molded finished sheets which are about 0.040 inch in thicknessemploying a molding cycle of three minutes at 160 C.

The light stability valuesset forth beloware obtained Patented dune 2,1959 after weatherometer exposure for 500, 750 and 1000 hours:

Results similar to those obtained from compositions B, C and D arerealized upon substituting cadmium diricinoleate, cadmium dibenzoate orcadmium phthalate', respectively, in substantially the same amount forcadmium dilaurate.

Compositions having similarly improved light stability properties areprepared by replacing the epoxy compound of compositions B, C and D,i.e. butyl, glycidyl phthalate, with substantially the same amount,respectively, of cyclohexyl-9,lO-epoxyoctadecanoate,methyl-9,10-epoxy-octadecanoate, glycidyl laurate, 2-ethylhexyl glycidyladipate, 1,2-epoxytetradecane and 1,2-epoxy-3-(2-naphthoxy) propane.

Employing in compositions B, C and D, respectively, instead of triphenylphosphite an equal weight of tricresyl phosphite similarly improvedlight stability results are obtained. Similar results are obtainedemploying trioctyl phosphite and tri-nonyl phosphite.

Other salicylic acid esters than the aforedescribed may be employed inconjunction With a tri(hydrocarbon) phosphite of this invention andprovide outstanding light stabilizing properties. As illustrative ofsuch as p-tolyl salicylate, m-tolyl salicylate, 4-tert. butylphenylsalicylate, Z-hydroxyphenyl salicylate, B-hydroxyphenyl salicylate,4-hydroxyphenyl salicylate, 4-rnethoxyphenyl salicylate,2,4-dihydroxyphenyl salicylate, 2-hydroxyphenyl 4- methoxy salicylate,2-hydroxy-4-methoxyphenyl 4-rnethoxy salicylate, and the like. Whilesalicylic acid esters are the preferred embodiment of this invention,other hydroxy benzoic acid esters when combined with a tri(hydrocarbon)phosphite of this invention provide light stabilizing properties. Asillustrative of such are phenyl m-hydroxy-benzoate, phenylp-hydroxy-benzoate, phenyl 3,4-dihydroxy-benzoate, phenyl vanillate,phenyl isovanillate, phenyl wresorcylate, phenyl ,B-resorcylate, phenylgentisate, and the like.

When a physical mixture of a tri(hydrocarbon) phosp'mte and a hydroxybenzoic acid ester of this invention 18 used as the light stabilizingsubstance for the heat stable compositions of U.S. 2,671,064, theamounts of the components may be varied considerably and still result insurprising improvements in light stability. For most purposes, however,0.05 to 10 parts of the hydroxy benzoic acid esters of this inventionand 0.1 to 5 parts of the tri(hydrocarbon) phosphite per parts byweightof halogen-containing resins will provide satisfactory results.

Ihe tri (hydrocarbon) phosphites used in the light stabilizer mixtureare of the structure s Where R R and R are like or unlike hydrocarbonradicals of a non-olcfinic character containing from 4 to 14 carbonatoms. For example they may he aryl radicals such as phenyl, tolyl,ethylphenyl, xylyl, cumyl, cymyl, xenyl, naphthyl and the like, or alkylradicals such as butyl, amyl, hexyl, octyl, decyl, dodecyl, or aralkylradicals such as benzyl, phenethyl, phcnpropyl, or any mixture of alkyl,aryl and alkaryl radicals. It is preferred that the hydrocarbonradicalbean aryl, aralkyl or saturated alkyl radical containing -from 6 to 12carbon atoms. The phosphite should be non-volatile under the conditionsof processing and be soluble in the halogencontaining resin. Specificexamples of phosphite contemplated are triphenyl phosphite, tricresylphosphite, phenyl dicresyl phosphite, cresyl diphenyl phosphite,tri(dimethylphenyl) phosphite, tributyl phosphite, trioctyl phosphite,trinonyl phosphite, tridecyl phosphite, tridodecyl phosphite, tribenzylphosphite, octyldiphenyl phosphite, phenyl dioctyl phosphite, etc.

On substituting for the polyvinyl chloride used in the foregoingexamples other halogen-containing resins, it is found that surprisinglyefiective light stabilization results are also obtained with such otherresins, numerous examples of which are well known to those skilled inthe art. Thus, for the polyvinyl chloride there may be substitutedresins made from such vinylidene compounds as vinylidene chloride, vinylchloracetate, chloro styrenes, chloro butadienes, etc. Such vinylcompounds may be polymerized singly or in a mixture with these or otherhalogen-containing vinylidene compounds or with vinyli dene compoundsfree from halogen. Among the unsaturated materials free from halogenwhich may be copolymerized with halogen-containing vinylidene compoundsare vinyl esters of carboxylic acids, for example vinyl acetate, vinylpropionate, vinyl butyrate, vinyl benzoate; esters of unsaturated acids,for example, alkyl acrylates, such as methyl acrylate, ethyl acrylate,propyl acrylate,

, butyl acrylate, allyl acrylate and the corresponding esters ofmethacrylic acid; vinyl aromatic compounds, for example, styrene,para-ethyl styrene, divinyl benzene, vinyl naphthalene, alpha-methylstyrene; dienes, such as butadiene, unsaturated amides, such as acrylicacid amide, acrylic acid aniline; unsaturated nitriles, such as acrylicacid nitrile; esters of 4:1,fl-UIIS3U1I8t6d carboxylic acids, forexample, the methyl, ethyl, propyl, butyl, amyl, hexyl, heptyl, octyl,allyl, methallyl, and phenyl esters of maleic, crotonic, itaconic,fumaric acids and the like. The class of copolymers in which apredominant portion, i.e., more than 50% by Weight, of the copolymer ismade from a halogen-containing vinylidene compound such as vinylchloride represents a preferred class of polymers to be treatedaccording to the invention.

Among the preferred embodiments of the invention is the stabilization ofpolymers prepared by the copolymerization of 95 to 80 parts by weight ofa. vinyl halide, e.g. vinyl chloride with 5 to 20 parts by weight of ana,fi-unsaturated polycarboxylic acid such as diethyl maleate or otheresters of maleic, fumaric, aconitic, itaconic acids, etc. Among thepreferred esters of such acids are alkyl esters in which the alkyl groupcontains not over 8 carbon atoms.

The light stabilizer mixture of the invention is also effective whenintimately mixed with halogen-containing resins in which part or all ofthe halogen is introduced into a preformed resin, e.g. chlorinatedpolyvinyl acetate, chlorinated polystyrene, chlorinated polyvinylchloride, chlorinated natural and synthetic rubbers, rubberhydrochloride, etc.

The light stabilizer mixture of the invention is also elfective inhalogen-containing resins containing halogens other than chlorine, e.g.,bromine, fluorine and iodine.

The halogen-containing resins may contain a varying proportion ofhalogen depending upon the nature of the resin and its contemplated use.However, as indicated above, vinyl chloride polymers in which theproportion of vinyl chloride units amount to 50% or more of the totalmonomer used in making the polymeric product represent a preferred classof polymers to be heat and light stabilized according to the invention.

Ordinarily as noted in US. 2,671,064 at least 1 part of the epoxycompound is used in stabilizing 100 parts of a halogen-containing resinfor most uses and generally, at

least 5 parts of the epoxy compound are preferred, al-

though smaller amounts are efiective to a considerable degree. Muchlarger amounts may be used, e.g. 50-100 parts, and serve to lengthen theuseful life of the halogencontaining resins although not in directproportion to the amount used. However, in some cases the epoxy compoundmay serve both as a plasticizer and an element of the stabilizer mixtureand in such cases it may be worthwhile to incorporate such largeramounts.

The epoxy compounds used in conjunction with the light stabilizermixture of this invention comprise organic compounds generallycontaining one or more groups. Various substituted and unsubstitutedaliphatic, aromatic, alicyclic and heterocyclic groups may be attachedto said epoxy groups. Generally, however, the epoxy compounds which areemployed should have a boiling point at atmospheric pressure of at leastC.', otherwise the stabilizing eifect islikely to be relativelytransitory due to evaporation of the epoxy compound and preferably theepoxy compounds should have a boiling point of at least 200 C. atatmospheric pressure. Illustrative examples of epoxy compounds which maybe used according to the invention are 1,2-epoxytetradecane, 1,2-epoxyoctadecane and other derivatives of long chain alkanes, forexample, alkanes having 10-24 carbon atoms having a group; epoxy esterscontaining a long carbon chain such as glycidyl laurate, methyl9,10-epoxyoctadecanoate, diethylene glycol, di-9,IO-epoxyoctadecanoate,9,10-epoxy octadecanyl acetate, 9,10-epoxyoctadecanyl octadecanoate,esters of polycarboxylic acids and alcohols containing a group such asdi-Z-ethylhexyl epoxy succinate, butyl glycidyl phthalate, diglycidylphthalate, propylene glycol diglycidyl phthalate, diethylene glycoldiglycidyl maleate, 2-ethylhexyl glycidyl adipate, hexyl glycidylscbacate and other esters of these and other polycarboxylic acidscontaining at least a group and epoxidized acids and esters generallycontaining an unsaturated longchain aliphatic group such as epoxidizedanimal, vegetable or marine oils or the fatty acids or mixtures of fattyacids contained in such oils and esters thereof, e.g., epoxidizedlinseed oil, epoxidized soybean oil, epoxidized oleic acid, epoxidizedtung oil, the methyl ester of epoxidized linseed oil fatty acids, etc.;glycidols such as glycidoLfl-methyl glycidol, fi-ethyl glycidol,S-hydroxy methyl glycidol, di-isobutenyl dioxide; epoxidized ethers suchas alkyl glycidol ethers in which the alkyl group contains 1-5 carbonatoms, e.g., methyl, ethyl, propyl, butyl, amyl glycidyl ethers;glycidyl ethers containing unsaturated groups such as vinyl, allyl andmethylallyl glycidyl ethers, phenyl glycidyl ether, tolyl glycidylethers, naphthyl glycidyl ethers, cyclopentyl glycidyl ether, cyclohexylglycidyl ether, etc. Other illustrative epoxy compounds includecyclohexane oxide, l-(Z-phenylphenoxy) propylene oxide-2,3,1-(2-phenylcyclohexanoxy) propylene oxide-2,3, l-(cyclohexanoxy)propylene oxide-2,3, 1-(2-cyclohexyl-phenoxy) propylene oxide-2,3,l-(4-tertiary butyl phenoxy) propylene oxide-2,3, styrene oxides such asstyrene oxide, para-ethyl styrene oxide, dimethyl styrene oxide,ortho-methoxy styrene oxide, 4- (2,3-epoxypropoxy) acetyl phenone, thecorresponding be p e on roaid ,4f-d tz,. pc yp p l benzephenone, mesityloxide epoxide; epoxy alkyl and epoxy cycloalkyl amides such as2-ethyl-3-propyl'glycidamide, 2,B-di-propylglycidamide; aryloxyalkeneoxides such as phenoxy propene oxide, para-tertiary amyl andpara-secondary amyl phenoxy propene oxides.

According to one embodiment of the invention the epoxy compounds areepoxy ethers such 'as the glycidyl ethers of such polyhydric alcoholsas. glycerin, d'iglycerol, erythritol, pentaglycerol, pentaerythritol,mannitol, sorbitol, polyallyl alcohol, polyvinyl alcohol, ethyleneglycol, propylene glycol, butylene glycol, etc.

One of the preferred classes of epoxy compounds comprises high molecularweight or resinous epoxy compounds, for example, those made by reactingpolyhydric phenols with epichlorhydrin in various ratios in alkalinesolution. Among the polyhydric phenols which may be used in preparingsuch glycidyl ethers are mono nuclear phenols like resorcinol, catechol,hydroquinone, etc., or polynuclear phenols likebis-(4-hydroxyphenyl)-2,2apropane (his-phenol), 4,4'-dihydroxybenzophenone, bis-(4- hydroxyphenyl) 1,1 ethane, bis (4 hydroxyphenyD-1,1-ethane, bis-(4-hydroxyphenyl)-1,l-isobutane, bis-(4- hydroxyphenyl)2,2 butane, bis (4 hydroxy 2- methylphenyl)-2,2-propane,bis-(4-hydroxy-2-tertiary butyl phenyl) 2,2 propane, bis (2dihydroxynaphthyl)-methane, 1,5-dihydroxy naphthalene, phloro glucinol,1,4-dihydroxy naphthalene, 9,10-dihydroxy anthracene, 1,3,6-trihydroxynaphthalene, 4,4-dihydroxy diphenyl, 2,2-bis l-hydroxy phenyl) propaneand 1,4-bis (4hydroxy phenyl) cyclohexane, etc. .Such phenols may bereacted with epoxy chlorhydrin in the presence of an inorganic alkalinematerial to form the epoxy compounds, which, depending upon theconditions of the reaction, may be either monomeric or polymericmaterials. Examples of such epoxy compounds'include 1,4-diglycidol epoxybenzenes and 2,2-bis (4-glycido1 oxyphenyl) propanes.

Other compounds containing a group which may be used in accordance withthe invention include those madeby reacting alkyl sulfonyl chlorideswith glycidol in the presence of ammonia wherein the alkyl groupcontains up to 20 or more carbon atoms, e-.g.

Usually the amount of the cadmium salt is smaller than that of the epoxycompound. While extremely small amounts of the cadmium salt have anoticeable efiect on the heat stability, usually at least 0.1 part per100 parts of halogen-containing resin is used and preferably at least0.5 part. Generally, not over 5-10 parts of the cadmium salt areadvantageously used although the use of 'more than parts for each 100parts of halogen-containing resin is not precluded. A preferred range is0.5-5 parts of cadmium salt for each 100 parts of resin.

Various cadmium salts of organic'acids may be used, examples of whichinclude those salts made'from such acids as saturated aliphatic-acids,e.g. ethanoic,--propanoic, butanoic, pentanoic, hexanoic, heptanoic,octanoic, nonanoic, decanoic, hendecanoic, dodecanoic, tetradecanoic,hexadecanoic and octadecanoic; mono-olefinic-unsaturated aliphatic acidssuch as propenoic acid, Z-butenoic acid, 2-methyl-2-propenoic acid,3-butenoic acid, 2-pentenoic acid, 4-pentenoic acid, Z-methyl-Z-butenoicacid, 2-hexenoic ac'id,7-'hexadecenoic acid, 10=undecenoic acid,l3-docosenoic acid, 2-hexenoic acid, and 9-octadecenoic acid; diolefinicunsaturated aliphatic acids such as 2,4- pentadienoic acid,2,4-hexadienoic acid, 3,7-dimethyl-2,6- octadienoic acid,9,12-octadecandienoic acid; triolefinicunsaturated aliphatic acids suchas 3,7-dimethyl-2,4,6- octatrienoic acid, 9,12,15-octadecatrienoic acid,9,11,13- octadecatrienoic acid; substituted olefinic acids, for example,such hydroxy olefinic acids as 2-hydroxy-3-butenoic acid,l6-hydroxy-7-hexadecenoic acid and l2-hydroxy-9-octadecenoic acid;acetylenic unsaturated aliphatic acids such as propynoic, butynoic,pentynoic, amyl propynoic, 7-hexadecynoic, 9-octadecynoic and13-docosynoic acids.

Mixtures of unsaturated aliphatic acids may be employed, as for example,mixtures of acids occurring in various oils, as for example, linseed,castor, tung, soya bean, perilla, corn, cotton seed, sunflower,safflower, sesame, poppy seed, walnut, peanut, olive, rape seed, whaleand dehydrated castor oils. The acids derived from these oils consistpredominantly of unsaturated acids containing 18 carbon atoms. Forcertain purposes, salts may be used which are made of the mixtures ofacids occurring in oils such as palm kernel oil, cocoanut oil and thelike, which mixtures of acids contain substantial amounts of unsaturatedacids such as those mentioned above, but do not predominate therein.

Other cadmium salts of organic acids may also be used such as cadmiumsalts of aliphatic polycarboxylic acids, e.g., cadmium salts of maleic,succinic, adipic and sebacic acids, etc., as well as polycarboxylicacids obtained by polymerization of unsaturated fatty acids, e.g., oleicacid dimer and linoleic acid dimer; salts of aromatic acids, e.g.cadmium salts of phenylacetic, benzoic, phthalic and salicylic acids;salts ofcyclic acids, e.g. the cadmium salt of abietic acid.

The cadmium salts may be either neutral or'basic salts whenmonocarboxylic acids are used. Mixed salts'made from mixtures of acidsmay also be used.

Of the various salts which'may he used in the heat stabilizercombination, -a preferred class comprises those made from ethylenicallyunsaturated fatty acids containing at least 10 carbon atoms, e.g.. 10-24carbon atoms, such as those mentioned above.

group, e,g. cadmium 'di-9,l0.-epoxy octadecanate and other cadmium saltsof organic acids containinga group such as those epoxy acids mentionedabove.

The heat and light stabilizer combination of this invention is ofparticular importance in stabilizing halogencontaining resins especiallyvinyl chloride polymers plasticizer with phosphate esters such as. thealkyl diaryl phospirates in which the alkyl group contains 6-14 carbonatoms and the aryl groups are phenyl or cresyl groups, i.e., ortho-,metaor paracresyl groups and mixtures thereof since compositionscontaining such plasticizers have proved to be especially difiiculttostabilize. Examples of such esters include 2 ethylhexyl diphenylphosphate, 2-ethylhexyl dicresyl phosphate, 2-ethylhexyl phenyl cresylphosphate, hexyl diphenyl phosphate, hexyl phenyl cresyl phosphate,hexyl dicresyl phosphate, dodecyl diphenyl phosphate, dodecylphenylcresyl phosphate, dodecyl dicresyl phosphate, etc. Mixtures of suchesters may frequently be used advantageously. The amount of thephosphate ester which is used may be substantially varied alkyl diarylphosphate esters may be employed as well as mixtures of such phosphateesters and such conventional plasticizers as dioctyl phthalate,tricresyl phosphate, butyl phthalyl butyl glycolate, etc. In the case ofcertain halogen-containing resins no plasticizers are required.

While this invention has been described with respect to certainembodiments, it is not so limited and it is to be understood thatvariations and modifications thereof may be made without departing fromthe spirit or scope of this invention.

What is claimed is:

1. A light stabilized vinyl halide polymer composition comprising avinyl halide polymer in which at least 50% of the monomer units arevinyl halide units, any balance being units of an ethylenicallyunsaturated monomer, 0.1 to 5 parts per 100 parts by weight of polymerof a tri(hydrocarbon) phosphite of the structure o-n; where R R and Rare hydrocarbon radicals free of olefinic unsaturation containing 4 to14 carbon atoms and 0.05 to 10 parts per 100 parts by weight of polymerof where n is an integer of from to 1, where m is an integer of from 1to 2, and where R is an aromatic radical consisting of carbon, hydrogenand oxygen atoms and whose cyclic nucleus is carbocyclic.

2. A light stabilized vinyl chloride polymer composition comprising avinyl chloride polymer in which at least 50% of the monomer units arevinyl chloride units, any balance being units of an ethylenicallyunsaturated monomer, 0.1 to 5 parts per 100 parts by weight of polymerof a tri(hydrocarbon) phosphite of the structure O-Rs where R R and Rare hydrocarbon radicals free of olefinic unsaturation containing 4 to14 carbon atoms and 0.05 to parts per 100 parts by weight of polymer ofa hydroxy substituted benzoic acid ester of the structure where R R andR are hydrocarbon radicals free of olefinic unsaturation containing 6 to12 carbon atoms and 0.05 to 10 parts per 100 parts by weight of polymerof m-hydroxyphenyl salicylate.

4. A composition resistant to the deteriorating efiects of heat andlight comprising a vinyl chloride polymer in which at least 50% of themonomer units are vinyl chloride units, any balance being units of anethylenically unsaturated monomer and as a stabilizer therefor (a) inheat stabilizing amounts 2. mixture of a cadmium salt of a carboxylicacid and an epoxy compound characterized by the grouping and (b) inlight stabilizing amounts in the range of 0.1

fi-O-di. 3 0 where n is an integer of from 0 to 1, where m is an integerof from 1 to 2, and where R is an aromatic radical consisting of carbon,hydrogen and oxygen atoms and whose cyclic nucleus is carbocyclic.

5. A composition resistant to the deteriorating effects of heat andlight comprising a vinyl chloride polymer in which at least 50% of themonomer units are vinyl chloride units, any balance being units of anethylenically unsaturated monomer and as a stabilizer therefor (a) inheat stabilizing amounts a mixture of a cadmium salt of a carboxylicacid and an epoxy compound characterized by the grouping and (b) inlight stabilizing amounts in the range of 0.1 to 5 parts per parts byweight of polymer of a tri (hydrocarbon) phosphite of the structureB1O'P o-R, wherein R R; and R are hydrocarbon radicals free fromolefinic unsaturation containing 6 to 12 carbon atoms and 0.05 to 10parts per 100 parts by weight of polymer of a hydroxy substitutedbenzoic acid ester of the structure the grouping and (b) in lightstabilizing amounts in the range of 0.1

to 5 parts per 100 parts by weight of polymer of a tri (hydrocarbon)phosphite of the structure wherein R R and R are hydrocarbon radicalsfree from olefinic unsaturation containing 6 to 12 carbon atoms and 0.05to parts per 100 parts by weight of polymer of metahydroxyphenylsalicylate.

7. The composition of claim 4 wherein. the cadmium salt is the cadmiumsalt of an ethylenically unsaturated fatty acid containing at least 10carbon atoms.

8. The composition of claim 7 wherein the halogen containing resin ispolyvinyl chloride.

9. The composition of claim 7 wherein the halogencontaining resin is avinyl chloride-vinyl acetate copolymer.

10. The composition of claim 7 wherein the halogencontaining resin is avinyl chloride-diethyl maleate copolymer.

11. The composition of claim 7 having as a plasticizer therefor aphosphate ester plasticizer, the said phosphate being present in amountsof 10 to 100 parts by weight per 100 parts of the vinyl chloridepolymer.

12. The composition of claim 11 wherein the phosphate ester plasticizeris an alkyl diaryl phosphate wherein the alkyl group contains from 6 to14 carbon atoms and the aryl group is a member of the class consistingof phenyl and cresyl radicals.

13. The composition of claim 12 wherein the tri(hydrocarbon) phosphiteis triphenyl phosphite.

14. The composition of claim 13 wherein the cadmium salt is cadmiumdirici-noleate.

15. The composition of claim 13 wherein the cadmium salt is cadmiumlaurate.

16. A composition resistant to the deteriorating eifects of ultravioletlight which comprises a vinyl halide polyture C-O-R where n is aninteger of from 0 to 1, where m is an integer of from 1 to 2, and R isan aromatic radical consisting of carbon, hydrogen and oxygen atoms andwhose cyclic nucleus is carbocyclic.

References Cited in the file of this patent UNITED STATES PATENTS2,464,250 Moll etal Mar. 15, 1949 2,469,696 Minsk et a1. May 10, 19492,477,609 Irons et a1. Aug. 2, 1949 2,564,646 Leistner et a1. Aug. 14,1951 2,572,571 Marling Oct. 23, 1951 2,671,064 Cowell et a1. Mar. 2,1954 2,752,319 Lipke et al. June 26, 1956 OTHER REFERENCES Schildknecht:Vinyl and Related Polymers, page 310, John Wiley, NY. (1952),,

1. A LIGHT STABILIZED VINYL HALIDE POLYMER COMPOSITION COMPRISING AVINYL HALIDE POLYMER IN WHICH AT LEAST 50% OF THE MONOMER UNITS AREVINYL HALIDE UNITS, ANY BALANCE BEING UNITS OF AN ETHYLENICALLYUNSATURATED MONOMER, 0.1 TO 5 PARTS PER 100 PARTS BY WEIGHT OF POLYMEROF A TRI(HYDROCARBON) PHOSPHITE OF THE STRUCTURE